Dressing- millstones



UNITED STATES PATENT OFFICE.

JOEL BOWMAN, OF SOMERSET, OHIO.

DRESSING MILLSTONES.

Specification of Letters Patent No. 28,553, dated June 5, 1860.

To all whom it may concern:

Be it known that I, JOEL BOWMAN, of Somerset, in the county of Perry andState of Ohio, have invented a new and useful Improvement in Machinesfor Dressing Mill-Burs; and I do hereby declare that the following is afull, clear, and exact description of the same, reference being had tothe annexed drawing, forming part of this specification, in the severalgures of which similar characters of reference denote the same art. pFigure l is a rear elevation of the machine. Fig. 2 is a verticalsection on m perpendicular to driving shaft. Fig. 3 is a verticalsection on y y, showing manner of removing traversing nut.

The nat-ure of this invention consists in combining with a dressingmachine constructed as hereinafter to be set forth, a device whereby thedepth 0f cut can be instantaneously regulated bythe operator during therunning of the machine; the details of construction and operation beingas follows.

In the drawing B is the bed plate, with ways a. a for the movement ofupper platform A; this movement being effected by the turning of screw Sthrough wheels Z) and c, the nut l being made to mesh with the thread bymeans of screw f; and remover therefrom by spring e when the pressure ofsaid screw is removed, this being for feeding the chisel forward, andbringing the platform back to its starting point.

The platform A has longitudinal ways g g for the traversing of thecarriage C. This is effected by screw S and nut it; the screw beingturned by the gear connection D D with the main cam shaft E. The chiselF is secured in the head of lever Gr, held in bearings at z', and isoperated by rods r acting on projection m of lever.

Secured to the carriage C, is a frame I, in which is hung a bar n,having a spring p reaching to the rear of lever Gr. This bar has alsoarms g jointed with rods t, running upward through a plate u on the topof frame I, and having a cross bar a@ upon the heads of said rods; aspring o keeping this movable frame tx, su'iciently elevated so as notto interfere with the movement of lever G under the action of reel It.When however, this frame t* is pressed down, spring p will prevent thechisel from making its full descent, and thus graduate the depth of cut.This is necessary when the chisel is over a soft spot in the stone whichcan be observed by the operator at the time the chisel is over it. I-Iethen presses upon the movable frame tx, turning bar n, and bringingspring p into action as above stated. The removal of pressure permitsthe chisel to resume its regular stroke. The amount of this graduat-ionis regulated by the amount of pressure on the sliding frame.

In other respects the operation of the machine does not differmaterially from ordinary machines of this character.

lVhat I claim and desire to secure by Letters Patent, is-

The application to the lever G of the graduating device consisting ofrocking bar n with arms g connected with sliding frame tx, incombination with springs p and 0),' the arrangement and operation beingsubstantially as set forth.

In testimony whereof I have hereunto signed my name before twosubscribing witnesses.

JOEL BOWMAN.

Witnesses GEO. PATTEN, JOHN S. HOILINGSHEAD.-

